USN-1140-1: PAM vulnerabilities

30 May 2011

An attacker could cause PAM to read or delete arbitrary files or cause it to crash.

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Releases

Packages

  • pam - Pluggable Authentication Modules

Details

Marcus Granado discovered that PAM incorrectly handled configuration files
with non-ASCII usernames. A remote attacker could use this flaw to cause a
denial of service, or possibly obtain login access with a different users
username. This issue only affected Ubuntu 8.04 LTS. (CVE-2009-0887)

It was discovered that the PAM pam_xauth, pam_env and pam_mail modules
incorrectly handled dropping privileges when performing operations. A local
attacker could use this flaw to read certain arbitrary files, and access
other sensitive information. (CVE-2010-3316, CVE-2010-3430, CVE-2010-3431,
CVE-2010-3435)

It was discovered that the PAM pam_namespace module incorrectly cleaned the
environment during execution of the namespace.init script. A local attacker
could use this flaw to possibly gain privileges. (CVE-2010-3853)

It was discovered that the PAM pam_xauth module incorrectly handled certain
failures. A local attacker could use this flaw to delete certain unintended
files. (CVE-2010-4706)

It was discovered that the PAM pam_xauth module incorrectly verified
certain file properties. A local attacker could use this flaw to cause a
denial of service. (CVE-2010-4707)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 8.04
Ubuntu 11.04
Ubuntu 10.10
Ubuntu 10.04

In general, a standard system update will make all the necessary changes.